ELECTROMAGNETIC-FIELD ANALYSIS OF FILM TRANSFORMER

In this paper, we investigate a thin film transformer for small electronic devices. This transformer is composed of the lamination of thin film conductors. Both the primary and secondary coils of the film transformer are arranged coaxially on one layer and multiply laminated. The operation principle of the transformer is based on the skin effect and the mutual effect between the coils at high frequency. Using the integral equation method, we evaluate the electromagnetic field and calculate the lumped circuit parameters, (e.g. inductance and resistance, etc.). A fairly good agreement is obtained comparing with experimental values. Thus, the applied method is quite useful for design and investigation of the thin film transformer.